Awnings of the type described above are known. In the usual case, the awning mechanism includes a carrier frame which is attached, for example, to the wall of a house or store front. The carrier frame includes extension arms, at the end of which there is disposed a drop tube. The extension arms may be changed in length. In order to insure that the drop tube tends to move away from the principal roller when the awning cloth is rolled off, the extension arms are so disposed as to cause the motion of the drop tube to be slightly inclined downwardly from a horizontal plane. In this manner, the effect of gravity causes the extension of the awning when the cloth is unrolled from the principal roller. In order to adapt the position of the awning to afford protection against various angles of incidence of sunlight, for example, it is known in the art to provide a capability to pivot the entire awning including a part of the carrier frame for the principal roller with respect to the wall to which it is attached and about a horizontal axis. In this manner, the entire awning may be inclined drastically with respect to a horizontal plane. A variable mechanism of this type requires an extraordinarily heavy and robust carrier frame however. A further disadvantage of the known mechanism is that when the awning is inclined substantially, the lower parts thereof may descend to the level of pedestrians and interfere with their free passage.